Re: [PATCH v5 12/21] libxl: use vchan for QMP access with Linux stubdomain

[Ian Jackson <ian.jackson@xxxxxxxxxx>]

Jason Andryuk writes ("[PATCH v5 12/21] libxl: use vchan for QMP access with 
Linux stubdomain"):
> From: Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>
> 
> Access to QMP of QEMU in Linux stubdomain is possible over vchan
> connection. Handle the actual vchan connection in a separate process
> (vchan-socket-proxy). This simplified integration with QMP (already
> quite complex), but also allows preliminary filtering of (potentially
> malicious) QMP input.
> Since only one client can be connected to vchan server at the same time
> and it is not enforced by the libxenvchan itself, additional client-side
> locking is needed. It is implicitly implemented by vchan-socket-proxy,
> as it handle only one connection at a time. Note that qemu supports only
> one simultaneous client on a control socket anyway (but in UNIX socket
> case, it enforce it server-side), so it doesn't add any extra
> limitation.

You might mention in your commit message libxl qmp client code already
has locking to avoid attempts to talk concurrently to the same qemu.

Acked-by: Ian Jackson <ian.jackson@xxxxxxxxxxxxx>

Thanks,
Ian.